>>41993180>>41993222It depends if it's a regular Pokemon or just there for 1 or 2 episodes. They were able to be faithful to Celesteela's lore since it was only a one-off. If a main character captured it they would have had to ignore the whole "it starts forest fires whenever it decides to move" thing.
Unless Jessie and James get scammed into making the fossilmons, I doubt a main character will own one.